The security of wireless and wireline communications is increasingly being compromised by eavesdroppers who capture subscriber access codes and then use these codes to impersonate otherwise legitimate users to facilitate entry into the accounts or resources of these unsuspecting users. Although current systems are capable of identifying a user, these systems do not distinguish between an authentic user and a fraudulent entity seeking unauthorized access.
For example, a common approach to subscriber authentication includes the use of personal identification numbers (PIN) or passwords. A disadvantage of this approach, however, is that the PIN code or password is a static element of the system since it is changed only periodically, and sometimes not at all. Consequently, once a static password or PIN code is captured by an eavesdropper, the code may then be used to impersonate an otherwise authorized user.
Conventional analog mobile cellular systems are also susceptible to fraudulent, unauthorized access since only subscriber identification, and not authentication, is performed. In particular, a mobile cellular system typically employs a Mobile Identification Number (MIN) and Electronic Serial Number (ESN) to identify an entity. However, the system does not verify that the user is authentic. Thus, cellular telephone "cloning" is made possible by an eavesdropper who captures the ESN/MIN parameters and impersonates the otherwise legitimate entity.